PORT-AU-PRINCE — The cholera epidemic in Haiti is the fault of U.N. peacekeepers who allegedly allowed raw sewage to leach into the nation’s largest river, a group says.

The Institute for Justice and Democracy in Haiti has filed a complaint with the United Nations alleging reckless actions on the part of peacekeepers from Nepal are behind the fast-moving epidemic that has infected 5 percent of the population and caused 6,000 deaths, ABC News reported Tuesday.

“The sickness, death and ongoing harm from cholera suffered by Haiti’s citizens are a product of the U.N.’s multiple failures,” states the complaint filed by the group, which represents more than 5,000 cholera victims and their families. “These failures constitute negligence, gross negligence, recklessness, and deliberate indifference for the lives of Haitians.”

“Once cholera is introduced, it is extremely difficult to eradicate,” the complaint says, noting that for a half century there was not a single case of cholera reported in Haiti. “The cholera epidemic is expected to persist in Haiti for at least several years.”

Anthony Banbury, the U.N. assistant secretary-general for field support, told ABC News the United Nations commissioned four independent studies but was unable to trace the origins of the outbreak.

“We don’t know if it was the U.N. troops or not,” Banbury said. “That’s the bottom line.”